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Using airborne remote sensing and in-situ observations to assess emissions of complex CH4 sources
Get PDFMethane (CH4) is the second most important anthropogenic greenhouse gas. Its atmospheric concentration is significantly influenced by human activities and has increased over the past years. The adverse effects of such a greenhouse gas on the climate system has identified need to control its emissions. However, an accurate assessment of the different emission sources by existing observations remains challenging. Consequently, the methane budget still has significant uncertainties, especially for local sources. In this study, an attempt was made to quantify emissions for areal sources and complex source regions (about 1 to 90 km2 in area) using passive remote sensing data and in-situ data. The data set was collected during the COMEX (CO2 and MEthane eXperiment) research campaign in California in 2014. It comprised observations of CH4 by airborne remote sensing non-imaging (Methane Airborne MAPper, MAMAP) and imaging (Airborne Visible / Infrared Imaging Spectrometer - Next Generation, AVIRIS-NG) instruments as well as aircraft in-situ observations of CH4 and carbon dioxide (CO2) with a Picarro greenhouse gas in-situ analyser. The main objective was the quantitative analysis of emissions from prominent CH4 sources such as landfills and oil fields and, if present, also accompanying CO2 emissions. In particular, the unique spectroscopic measurements in the short wave infrared region from the MAMAP remote sensing instrument have successfully been used for this purpose. This was also the first time that CH4 emissions from an entire landfill and an oil field complex were quantitatively estimated from airborne remote sensing data. Elevated CH4 concentrations (or 'CH4 plumes') were detected downwind from landfills and across oil fields by remote sensing aircraft surveys using the MAMAP instrument. Following each remote sensing survey, the detected plumes were sampled within the atmospheric boundary layer by in-situ instruments on the same aircraft for atmospheric parameters such as wind information and dry gas mole fractions of CH4 and CO2. These measurements facilitated an independent assessment and verification of the surface fluxes. During the COMEX campaign, four landfills in the Los Angeles Basin were surveyed, where one landfill repeatedly showed a clear emission plume on four flight days. Additionally, an oil field complex in the San Joaquin Valley was investigated on seven days. Emission rates estimated from the MAMAP remote sensing and Picarro in-situ observations via mass balance approaches vary between 11.6 and 17.8 ktCH4/yr for the landfill, and between 31.0 and 47.1 ktCH4/yr for the oil field complex for several overpasses. Case-dependent relative uncertainties are between 17% to 45%. Furthermore, the in-situ and remote sensing based emission rates agree well within the error bars. The reported inventory value of the landfill of 11.5 ktCH4/yr for 2014 by the US Environmental Protection Agency (EPA) is on average 2.8 ktCH4/yr lower than the top-down estimate from this study. The top-down estimates of the oil field complex are consistent with the latest inventory estimate but can differ significantly if basic assumptions of production rates and emission factors are used yielding only around 6 ktCH4/yr. The imaging capabilities of the AVIRIS-NG instrument aboard a simultaneously flown second aircraft additionally allowed the identification of a possible leak in the landfill cover and the exact source positions of the emitters across the oil field complex
The Future of Employment on the Shop Floor: Why Production Jobs are Less Susceptible to Computerization than Assumed
Get PDFContext: Germany is seen as one of the major players in developing what is known as Industry 4.0. Especially in the manufacturing and the automotive sector, the vocational training is seen as a precondition and consequence alike for the global success of these sectors. Current research though characterizes production work, especially machine-related tasks, as dull routine work and therefore of high probability of computerization. Approach: Based on qualitative research perspectives and sociological results that reveal the importance of experience and implicit capabilities, this study quantifies what is mostly seen as non-routine work. To measure these dimensions of living labouring capacity, an index is introduced that is developed from 18 items of one of the biggest German task-based, representative surveys. Findings: The contribution challenges the widespread prognosis that production workers face high susceptibility. Comparing data on non-routine share in production and of vocational trained workers with those of Frey and Osborne, the findings stress the mostly neglected importance of non-routine work, even in production and especially with vocational trained, machine-related occupations. Conclusion: The results draw on how much more employees on the shop floor are apt to handle change, complexity, and imponderabilities than often assumed. If their work will or will not be susceptible to novel approaches in robotics or algorithms, therefore, is not a question of routine
Binding affinities and adhesion phenomena of binding peptides at the interface to zinc oxide
Get PDFPeptide sequences can selectively bind to inorganic substrates in a process similar to the concept of molecular recognition. Here we focused on zinc oxide as an important representative of functional oxides and identified binding peptides with an affinity for different ZnO facets. Five peptides were selected and their conformational ensemble (macrostate) and sensitivity to adsorption were characterised via circular dichroism (CD) spectroscopy. The microstates within their conformational ensembles are accessed by enhanced sampling simulations. To quantify the free energies of adsorption, an optically sectioned indicator displacement assay (O-IDA) was adapted to the peptide/ZnO interface and compared to the results of single molecule force spectroscopy (SMFS), leading to a good agreement between the two approaches
Understanding and fulfilling information needs of stakeholders along product lifecycles: Applying data analytics in product life-cycle management
Get PDFImproving the management of product lifecycle is becoming increasingly important today. The concept of Closed Loop Product Lifecycle Management (CL-PLM) has been developed to help organizations in the value chain to promote the comprehensive management of product lifecycle information and activities. CL-PLM attempts to manage all processes related to products, from product design to end of product life. However, the development of this concept is not still complete. There is a need for more research to manage the data and information flows and to provide each organization in the value chain with the right data from product Middle Of the Life (MOL). In this thesis, a new approach is presented, which completes the concept of CL-PLM in terms of information requirements of product beneficiaries in MOL of the product. The research question is as follows: Which groups and organizations use the products or are affected by it and can be benefited from the product's operational information? The research involves the determination of the information needs of the stakeholders and tests the automatic provision of information to stakeholder organizations (beneficiaries) using data analytics methods. The methodology used in this thesis is an inductive approach. To this end, two case studies on engineered products are carried out. Based on these two studies, the stakeholders involved in MOL, which benefit from the product and its information, are identified. Next, the dissertation identifies current and future information needs. Interviews and surveys have been used to identify information that MOL stakeholders need. The second part of this thesis examines, which data analytics methods can be useful for supporting each information need. After the completion of analysis, the findings are tested and implemented in real-world scenarios. The scenarios show how these information requirements can be satisfied with data analytics. The findings of this research are various. First is to find out the MOL stakeholders of the product lifecycle and grouping the most influential ones, which are affected by product MOL data and information. Moreover, identifying their current and potential future information needs from the product MOL. Second is a classification of data analytics tools (suggestions on suitable tools) that can help the stakeholders to meet their new information needs from the product, or improve their access to product MOL information. The third part of the results is the implementation of the mentioned concept in three scenarios. In implementation part, information needs of OEM about the performance of a component in an electric vehicle, information need of maintenance provider from motorboat in respect of spare part supply and information need of wind farm operator from windmills for contact design are selected and modeled. The latter shows that it is possible to automatize the provision of the required information to the stakeholders. These three contributions form the output of this dissertation. In sum, the findings of this thesis can be helpful for product and service manufacturers, especially those who want to move from pure production to the production of a product with the services, and organizations, who wish to add intelligence to their products. This research can also be useful for PLM software developers. Finally, it is helpful for all companies involved in the realization of engineered products that want to understand and manage the lifecycle of the product
Klimawandelbewusstsein und Akzeptanz erneuerbarer Energien
Get PDFThe EEG promotion led to an expansion of decentralised wind power and biogas plants throughout the northwest region of Germany. Without a broad socio-political acceptance of this development, the transformation to a climate-friendly energy supply system is facing a major hurdle. This dissertation contributes to research on social acceptance of renewable energies by showing that climate change awareness increases the acceptance, and that as a background variable, can increase or mitigate the effects of the perceived advantages and disadvantages of plants. For this, a postal cross-sectional survey with 577 respondents was carried out in the northwest region based on a registration office sample. The results showed that climate change awareness had a greater total effect on the acceptance of regional wind power plants than the perceived economic benefits, landscape effects or electricity price increases. The structural equation model for biogas plant acceptance showed climate change awareness as a less relevant predictor. Therefore, in the future, integrative studies on acceptance of renewable plants should consider the impact of climate change awareness
Kooperative Errichtung der Offshore-Windenergie : Konzeptionelle Entwicklung einer lieferketten- und projektübergreifenden Logistikgestaltung
Get PDFIn this thesis, the topic of planning and control in the network of the construction phase of offshore wind energy is considered. The needs of the industry for change and optimisation motivate a scientific discourse that goes beyond existing boundaries. The result of this work comprises the proof of the efficiency increase potentials by resource and information sharing in the construction phase of offshore wind energy by means of simulation, the definition of the requirements for a solution approach for the collaborative design and cooperative execution of the construction, a concept for the realization of these potentials, as well as the empirically supported development of the success factors for the implementation of the developed approach in practice
Der Blick des Kindes auf die Leinwand und die Welt
Get PDFAnalyse von Der Geist des Bienenstocks (Victor Erice, 1973) in Hinblick auf die ästhetische Darstellung des kindlichen Blicks und die Reflexion der Rolle des Kinos in der Kindheit
Online-Lerntheater - Neue Gestaltungsmöglichkeiten für das selbstgesteuerte Online-Lernen durch den Transfer einer alten Kulturtechnik auf den virtuellen Lehr- und Lernraum : Entwicklung, theoretische Fundierung, Analyse und Empirie
Get PDFSince theatre is successful as an old cultural technique, it is assumed that transferring its principles to online teaching can also make online learning more successful. This paper therefore deals with the question of whether certain methods and means of theatre are didactically suitable for use in online self-learning environments in order to develop a teaching method. The aim is to improve the motivation of learners in online learning and to integrate less used forms of knowledge and learning. For this purpose, the idea of an online learning theatre is theoretically founded, further developed, analysed and empirically investigated. An empirical comparison has shown that online learning theatre has led not only to stronger motivation but also to better performance and a deeper understanding of the learning material. In addition, it is also very suitable for the stronger integration of emotions and a more personal approach to learners, which is desired in eLearning but has so far rarely been implemented
Surface structures and taxonomy of marine Flavobacteriia
Get PDFFlavobacteria play a major role in the turnover of organic matter in the ocean. Their importance in the degradation of algal biomass was revealed by the dynamics of heterotrophic bacterial populations during the degradation of an algal bloom in the North Sea near Helgoland. Isolation of bacterial strains from seawater of the bloom allowed pure culture studies and visual examination of the bacteria, with strain Hel3 A1 48 showing unexpected surface extensions. In this study, the cell appendages of the flavobacterial strain Hel3 A1 48 were investigated for their morphology, composition and conditions of formation to reveal the unique properties these surface extensions may provide for the cells. All applied electron microscopic methods (SEM, TEM, thin section TEM and cryo-EM) showed the appendages as membrane tubes or vesicle chains of outer membrane origin. These up to 10 micrometer long chains were composed of vesicles being 80-100 nm long and 50-80 nm wide. Sometimes larger vesicles (160-250 x 130-200 nm) were present that included parts of the inner membrane and cytoplasm (O-IMVs). A model for formation was proposed starting with the outward-bulging of outer membrane and subsequent elongation as tube which later transformed into a chain of vesicles by an abiotic process called 'pearling'. In some cases the inner membrane was pulled together with the outer membrane tube and an O-IMV was formed. Electron microscopic visualization at different stages of growth and culture conditions revealed an increased production towards the stationary growth phase and did not show a condition without appendage production. Fluorescein-labeled laminarin uptake into the periplasm of the cells according to the 'selfish' uptake mechanism was visualized by SR-SIM. Staining was also observed in the vesicle chains. Proteomic analyses of total membrane fractions and of vesicle fractions confirmed the outer membrane origin by enrichment of outer membrane and extracellular surface-associated proteins in the vesicle fractions. Especially enriched were porins, TonB-dependent receptors and type IX secretion system components and secreted LPS anchored surface proteins. The appendages of strain Hel3 A1 48 enlarge the surface area of the cell and allow a larger number of surface-associated degradation enzymes and an additional periplasmic storage space. Strain Hel3 A1 48 was described taxonomically together with three other North Sea isolates. Two of the Helgoland strains (Hel3 A1 48 and Hel1 33 131) were isolated from the summer or spring bloom 2010, respectively. They differed in biochemical and physiological traits from each other and other type strains of related genera and were clustering together as a separate branch in phylogenetic trees, thus forming a new genus in the Flavobacteriaceae. The names Fragilitenera margaritagerula gen. nov., sp. nov., and Fragilitenera forsetii sp. nov., are tentatively proposed. Strain Hel1 31 208, isolated from the spring bloom 2010 near Helgoland, has a 98.6% 16S rRNA gene sequence identity to the newly described genus Arcticiflavibacter. Due to differences in biochemical and physiological characteristics, a new species, Arcticiflavibacter funis sp. nov., is tentatively proposed. Strain TFI002, isolated from Sylt seawater in autumn 2013, belongs to the family of Cytophagaceae and formed in the 16S rRNA tree a separate branch, clustering next to the genera Jiulongibacter and Taeseokella. The strain represents a new genus for which the name Simonia syltensis gen. nov., sp. nov., is tentatively proposed. All three flavobacterial strains isolated from Helgoland possess extracellular structures and all four have the TonB-dependent transport system and the major components of the type IX secretion system. Within the guild of bacteria that degrade polymers with surface enzymes (selfish mode), strain Hel3 A1 48 and other bacteria with similar surface appendages are expected to have an advantage in their nutrient acquisition
Natural Variability of Arctic and Antarctic Sea Ice : Insight From Pre-industrial CMIP5 Runs
No full textUnderstanding natural variability of Arctic and Antarctic sea ice is important for explaining and predicting observed sea ice variability. Motivated by this, I undertook this study that analyzes sea ice variability in pre-industrial control runs for a subset of Earth System Models (ESMs) and Climate Models (CMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5), and the Alfred Wegener Institute Climate Model (AWI-CM). I compare the general characteristics of simulated mean sea ice conditions in the Arctic and Antarctic for the selected models. I find that the main characteristics of Arctic sea ice are better simulated than that of Antarctic sea ice. None of the selected models were able to simulate all of the Antarctic sea ice characteristics properly.Inter-model spread of winter sea ice volume and summer sea ice extent in both hemispheres is large, with the spread exceeding the limits of natural variability. The drivers of the Arctic sea ice minimum in September and the Antarctic sea ice minimum in February are studied using composite analysis. In the Arctic, events of low sea ice extent in September are related to (1) Sea Ice Thickness (SIT) Memory (2) a negative Sea Level Pressure (SLP) and a positive Sea Surface Temperature (SST) anomaly in the Barents Sea in March, (3) the deepening of the Aleutian Low in March with imprints of ENSO and PDO, and (4) a positive SLP anomaly in the Beaufort Sea in July. I also find that events of low September sea ice extent minima tend to cluster in time. I suggest that in addition to low frequency climate variability, clustering of low September sea ice extent events depends on the memory of the Arctic sea ice system provided by SIT and ocean surface heat content. The occurrences of the aforementioned atmospheric patterns are random, in the sense that they are not necessarily taking place in the same years. An important characteristic of the events analyzed is an anomalous thin Arctic sea ice cover in winter that preconditions these late summer events. The anticyclonic SLP anomaly in the Beaufort Sea develops in summer, so if the sea ice cover is in a fragile and weak state, atmosphere-sea ice coupling will be even more efficient in reducing sea ice extent via Ekman convergence. In the Antarctic, events of low sea ice extent minimum in February are related to (1) a positive anomalous Southern Annular Mode (SAM) in winter that enhances sea ice divergence creating widespread negative anomalies in Sea Ice Concentration (SIC), (2) a negative anomalous SAM in summer and (3) a broad positive SST anomaly in the Southern Ocean associated with the negative SAM and SIC decline. Similar to the Arctic, events of low February sea ice extent minima tend to cluster in time, however with a lower likelihood of a February sea ice extent event to be followed by another. The memory of clustering in the Antarctic is provided by low frequency variability and the memory of the sea ice system that is predominately associated with ocean surface heat content anomalies. In both hemispheres, the reduction of sea ice extent and volume in years characterized by a low sea ice extent minimum, causes a strong negative net Short Wave Radiation (net SWR) anomaly in spring. This leads to enhanced sea ice melt via the positive sea ice-albedo feedback. From the composite analysis I suggest that the mechanism for producing low sea ice extent minima events in both hemispheres are similar. Such a mechanism involves the thinning of the sea ice cover in winter, enhanced sea ice albedo feedback in spring, and the efficient role of an anomalous anticyclonic SLP pattern in summer